The present invention relates to a synchronization system, and more particularly to one for use with a DVTR (digital video tape recorder).
In a DVTR, parallel digital words representing picture samples are converted into serial form for recording on tape. When the serial data is replayed and reconverted into parallel data, it must be operated on in the correct sequence, so that the bits of reconstructed parallel data retain the proper sequence of bits, i.e., MSB (most significant bit) to LSB (least significant bit). This type of synchronization (sync) is known as "bit sync," since it is the synchronization required to identify the MSB of a sample. In a DVTR, bit sync may be lost due to the occurrence of a signal dropout due to the skipping of a track in a search mode. Bit sync can also be lost due to a dropout even when no track skipping occurs if the clock extractor does not have a sufficient "flywheel" effect. Further even with analog recording when in the search mode, line sync can be lost. This leads to a degraded picture upon display.
It is therefore desirable to provide a system that uses all possible valid information to make up the resulting reproduced signal to avoid degradation thereof.